1. Field of the Invention
The present invention relates generally to the field of telecommunication equipment and technologies. More particularly, the present invention relates to the field of method, program and apparatus for secured facsimile transmissions.
2. Description of the Prior Art
Facsimile transmissions are very common in the business world today. In the most cases, facsimile transmissions are replacing regular mail (or UPS® and FedEx®), because the recipient receives the messages within minutes instead of hours or days or weeks.
Oftentimes sensitive information (such as technical drawing of an invention, financial or personal business data) needs to be transferred to a receiving party by facsimile transmission. However, it is very often the case that the fax device is accessible by many people for instance in a big office room or hotel. So the staff member can view the contents of the fax before it arrives the intended recipient. Having sensitive information viewed by unintended viewers can result in extremely negative consequences for an individual, company or government.
Another well known problem is industrial espionage which leads to annual losses of billions of dollar because of the fact that all fax transmission on a public network are done in a standard form (CCITT), easy to read like plaintext and therefore easy to intercept.
Another scenario is drawn when a fax does not arrives at the valid recipient because of a mistyping of the fax number, pressing the wrong speed dial key or an error in the telephone network. In this case, sensitive information goes into the wrong hands, which can lead to harm.
As a result, secured facsimile transmission becomes more and more important and a desired way of transmitting a document over a public telephone network. The following prior art references are found to be pertinent to this field of art:    1. U.S. Pat. No. 4,091,423 issued to Branscome on May 23, 1978 for “Synchronous Digital Data Scrambling System” (hereafter the “Branscome Patent”);    2. U.S. Pat. No. 5,159,630 issued to Tseng et al. on Oct. 27, 1992 for “Facsimile Message Encryption System” (hereafter the “Tseng Patent”);    3. U.S. Pat. No. 5,241,595 issued to Kuno on Aug. 31, 1993 for “Communication Control Section For Facsimile Equipment Having A Secure Communication Function” (hereafter the “Kuno Patent”);    4. U.S. Pat. No. 5,555,307 issued to Le Cone et al. on Sep. 10, 1996 for “Device and Process for Rendering Secure the Transmission of Faxes As Well As Fax Unit Which Has Been Made Secure and Incorporating Such A Device” (hereafter the “Le Cone Patent”);    5. U.S. Pat. No. 5,692,048 issued to Gormish et al. on Nov. 25, 1997 for “Method and Apparatus for Sending Secure Facsimile Transmissions and Certified Facsimile Transmissions” (hereafter the “Gormish Patent”);    6. U.S. Pat. No. 5,920,625 issued to Davies on Jul. 6, 1999 for “Method and Apparatus for Transmitting and Receiving Encrypted Signals” (hereafter the “Davies Patent”);    7. European Patent Application Publication No. 0-625-845-A1 published on Nov. 23, 1994 for “Ciphering Device and Method in Facsimile” (hereafter “EP 0-625-845-A1”);    8. United Kingdom Patent Application Publication No. GB-2-305-813-A published on Apr. 16, 1997 for “Data Encoding In Facsimile Systems” (hereafter “UK 2-305-813-A”);    9. PCT Patent Application Publication No. WO-98/21880 published on May 22, 1998 for “Method and System for Ensuring the Security of Fax Transmission Using An Identifying Card” (hereafter “PCT WO-98/21880”);    10. European Patent Application Publication No. EP-1-045-574-A1 published on Oct. 18, 2000 for “Method and Apparatus for Sending or Receiving A Secure Fax” (hereafter “EP 1-045-574-A1”); and    11. PCT Patent Application Publication No. WO-00/67466 published on Nov. 9, 2000 for “System of Providing Secure Transmission for Facsimile Data Modem Signals” (hereafter “PCT WO-00/67466”).
The Branscome Patent discloses a system for scrambling digital signals transmitted between a synchronous data transmitting station and a receiving station. The system includes a first scrambler and a second scrambler. When the scrambling system is used with a facsimile system, a first scrambler is connected between the video amplifier and the transmitter modulator of the transmitting facsimile station. The first scrambler includes digital circuitry for digitizing the output of the amplifier and enciphering circuitry for enciphering the digitized output of the video amplifier and for transmitting the enciphered output to the receiving facsimile station. A second scrambler is connected between the demodulator and the write amplifier of the receiving facsimile station. The second scrambler includes deciphering circuitry for deciphering the output of the demodulator and for applying the deciphered output to the write amplifier to provide a duplicate of the transmitted facsimile material. Initialization between the first and second scrambler is accomplished with the use of correlation and prime patterns. Circuitry is provided to maintain the first and second scramblers in synchronization with one another, and alarm systems are provided to indicate malfunction of the scramblers and to prevent the transmission of the scramblers and to prevent the transmission of sensitive data in the unciphered state.
The Tseng Patent discloses a system for maintaining the security of information transmitted between facsimile machines. The system includes a transmitting/receiving facsimile machine for receiving input sheets having an encryption zone; an image sensor for detecting the encryption zones; an encryption device for scrambling messages that appear within an encryption zone. Further the system includes means for sensing encryption zones on transmitted messages and for decoding messages that have been scrambled within the encryption zones.
The Kuno Patent discloses a facsimile equipment. The facsimile equipment includes a memory for storing a cipher key data, ten number keys for inputting the cipher key data, a DTMF signal receiving circuit for converting a DTMF signal received through a telephone line into the cipher key data, a controller for controlling the memory to selectively store the cipher key data input by means of the ten number keys or the cipher key data converted by the DTMF signal receiving circuit, a DTMF signal generating circuit for converting the cipher key data stored in the memory into a DTMF signal and generating this DTMF signal to the telephone line, and a controller for scrambling an image data to be transmitted with the cipher key data stored in the memory to provide the transmission data and for descrambling the scrambled image data received with the cipher key data stored in the memory to provide the reception data.
The Le Cone Patent discloses a device and process for securing the transmission of telecopies or faxes and a secured telecopier or fax unit having such a security device. The device incorporates a user interface permitting the establishment of a dialogue therewith and a security module permitting the production and checking of digital signatures and preventing replay.
The Gormish Patent discloses a facsimile transmission system with a first facsimile machine that includes at least a scanner for scanning documents inserted into a document feeder and transmission capabilities for sending a fax and with a second facsimile machine that includes at least reception capabilities for receiving the fax and a printer for printing a hard copy of the received fax, if necessary. The facsimile system may include functionality for securing the facsimile transmission. The facsimile system may include functionality to enable the facsimile transmission to be certified.
The Davies Patent discloses an encrypted signal compatible with first and second encryption systems which is generated by producing encryption data signals relating to each encryption system. A difference signal is derived from the two encryption data signals and the signal to be encrypted is encrypted in accordance with one of the encryption systems. At an output the encrypted signal, the two encryption signals, and the difference signal are made available. At a decoder compatible with, for example, the first encryption system, the encrypted data, the second encryption data signal, and the different signal are received. The decoder can then derive the first encryption data signal from the second encryption data signal and the difference signal and can then decode the encrypted signal.
EP 0-625-845-A1 discloses a ciphering device in a facsimile apparatus. The ciphering device is provided in which a signal to be ciphered comprising a coded signal and a control code added thereto is ciphered in units of n bits. The device comprises means for judging whether or not the total number of bits composing the signal to be ciphered is a multiple of n, and means for adding random data behind the signal to be ciphered so that the total number of bits composing the signal to be ciphered is a multiple of n and ciphering a signal comprising the signal to be ciphered and the random data added thereto in units of n bits when the total number of bits is not a multiple of n.
GB 2-305-813-A discloses a data encoding method for a facsimile system. According to the method, image data is scanned from a document and subsequently Modified Huffman or Modified Read encoded. The encoded data is XORed with a previously registered password prior to transmission. The encoded data is modulated into an analog signal and output to a line interface unit. As the process encodes and decodes image data using a registered password, it is able to improve the security of data.
PCT WO-98/21880 discloses a method and system for safely transmitting a fax between a transmitter sending the fax and at least a receiver receiving the fax using a fax machine associated with a telephone equipment. The faxes are routed between a transmitter and a receiver by a communication network via a fax management center. The fax management center provides the receiver with a card, formatted like a credit card, personalized by specific identifiers for each card and each receiver. This card emits brief identifying sound signals, of the DTME type, at least partially encrypted, varying with each operation, when it is actuated by the receiver. The signals received by the microphone of the telephone equipment are transmitted by the communication network to the computer services of the fax management center. The transmitted signals and the identification data of the receiver and of the card held by the computer services, are electronically processed and compared by the computer service of the fax management center. In the event of coincidence, the fax management center transmits to the fax machine of the receiver the fax sent to him by the transmitter.
EP 1-045-574-A1 discloses a method and apparatus which sends an encrypted FAX document to a receiving party. The encrypted FAX is printed out by a receiving FAX with an unencrypted heading, indicating who the intended recipient of the received encrypted FAX is, and a body of the FAX in an encrypted format. Once the intended recipient receives the encrypted FAX document, the document can be scanned and decoded after the intended recipient provides a decode code. The decoded document can be printed by or viewed on a computer.
PCT WO-00/67466 discloses a security system which operates to secure the transmission of data between authorized modems and against interception by an unauthorized modem. The modems each implement a defined protocol that includes negotiation and data transport portions of a communications session that is conducted over a network utilizing signals. selectively occurring in a plurality of frequency channels. The security device includes a first interface coupleable to a modem to exchange first predetermined signals occurring in a first plurality of frequency channels and a second interface coupleable to a network to exchange second predetermined signals occurring in a second plurality of frequency channels. A signal processor is coupled between the first and second interfaces, to implement a bidirectional conversion of the signals between the first and second plurality of frequency channels by frequency shifting the first and second predetermined signals between the first and second pluralities of frequency channels. Further, the security device can provide for a first frequency shift of greater than a predetermined frequency tolerance specified by the defined protocol for a first portion of said communications session and a second frequency shift for a second portion of the communications session.
While various approaches have been developed in connection with secured facsimile transmission, they present certain limitations and drawbacks. For example, the method disclosed in UK application requires special fax machines on both the sending and receiving ends of the transmission and is not compatible with existing conventional fax protocols. Therefore, it is desirable to have a method, program and apparatus for sending and receiving fax documents in a secured manner which is still compatible with existing fax protocols.